The 20-hour countdown for the launch of the prestigious second lunar mission, Chandrayaan-2, which willtake a billion dreams to the Moon, commenced at the spaceport of Sriharikota on Sunday evening.
The countdown started at 1843 hrs evening, ISRO tweeted.
''The launch countdown of #GSLVMkIII-M1/#Chandrayaan2 commenced at 1843 hrs. The launch is scheduled at 1443 Hrs IST on July 22nd'', the tweet said.
The launch preparations were progressing smoothly.
The 43.43 m tall GSLV-MkIII-M1, India's heaviest rocket thus far, carrying the 3,850kg Chandrayaaan-2, with Orbiter, (Vikram)-Lander and (Pragyan)-Rover as payloads for a soft landing on the Moon's South pole, would lift off from the Second Launch Pad at 1443 hrs on Monday afternoon.
ISRO said the Launch rehearsal has been completed and the performance was normal.
The launch was earlier scheduled on July 15, but was deferred an hour before the lift off off due to a technical snag in the three-stage launch vehicle.